more glade fixes for gtk4

safeeyes/glade/about_dialog.glade

@@ -160,14 +160,9 @@ along with this program.  If not, see &lt;https://www.gnu.org/licenses/&gt;.</pr
                 <property name="focus-on-click">False</property>
                 <property name="receives-default">True</property>
                 <property name="halign">center</property>
-                <property name="relief">none</property>
+                <property name="has-frame">0</property>
                 <property name="uri">https://github.com/slgobinath/SafeEyes?tab=readme-ov-file#how-you-can-help-improving-translation-of-safe-eyes</property>
               </object>
-              <packing>
-                <property name="expand">False</property>
-                <property name="fill">True</property>
-                <property name="position">2</property>
-              </packing>
             </child>
           </object>
         </child>

safeeyes/glade/required_plugin_dialog.glade

@@ -20,7 +20,7 @@
 ~ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 -->
 <interface>
-  <requires lib="gtk+" version="3.12"/>
+  <requires lib="gtk" version="4.0"/>
   <object class="GtkWindow" id="window_required_plugin">
     <property name="title" translatable="1">Safe Eyes - Error</property>
     <property name="resizable">0</property>
@@ -71,7 +71,10 @@
             </child>
             <child>
               <object class="GtkLabel" id="lbl_main">
-                <property name="margin">5</property>
+                <property name="margin-top">5</property>
+                <property name="margin-bottom">5</property>
+                <property name="margin-start">5</property>
+                <property name="margin-end">5</property>
                 <property name="wrap">1</property>
                 <property name="justify">center</property>
                 <property name="max-width-chars">60</property>

safeeyes/ui/required_plugin_dialog.py

@@ -40,7 +40,7 @@ class RequiredPluginDialog:
         builder = utility.create_gtk_builder(REQUIRED_PLUGIN_DIALOG_GLADE)
         self.window = builder.get_object('window_required_plugin')
 
-        self.window.connect("delete-event", self.on_window_delete)
+        self.window.connect("close-request", self.on_window_delete)
         builder.get_object('btn_close').connect('clicked', self.on_close_clicked)
         builder.get_object('btn_disable_plugin').connect('clicked', self.on_disable_plugin_clicked)
 
@@ -64,7 +64,7 @@ class RequiredPluginDialog:
         """
         Show the dialog.
         """
-        self.window.show_all()
+        self.window.present()
 
     def on_window_delete(self, *args):
         """